ECG of the Week – 24th September 2018 – Interpretation

This ECG is from a 15 year old male who presented with episodes of symmetrical hands turning cold and blue (symmetrically) which lasted for a few hours before improving. No prior past medical history, no regular medications. Very fit and active.

Interpretation:The combination of abnormal R wave transition, complete lead inversion leads V2 & V5 plus extreme axis should always alert us to the possibility of lead reversal.This is clearly not a ‘simple’ reversal i.e. only 2 leads misplaced but far more complex. The odds of every lead being attached to a patient incorrectly is very small but the connection between the leads and the machine is much easier to misconnect especially when old and worn. This what happened in this case with the connecting terminal for all the leads was placed upside down into the ECG machine with resultant lead swaps as below.Expected lead Actual leadRL RLRA V6V1 V1V2 RAV3 V5V4 V4V5 LAV6 V2LA V3LL LL

Once corrected the patients subsequent ECG was entirely normal !References / Further Reading